/*

 * Licensed to the Apache Software Foundation (ASF) under one

 * or more contributor license agreements.  See the NOTICE file

 * distributed with this work for additional information

 * regarding copyright ownership.  The ASF licenses this file

 * to you under the Apache License, Version 2.0 (the

 * "License"); you may not use this file except in compliance

 * with the License.  You may obtain a copy of the License at

 *

 *     http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package com.bff.gaia.unified.sdk.nexmark.sources.generator.model;



import com.bff.gaia.unified.sdk.nexmark.model.Bid;

import com.bff.gaia.unified.sdk.nexmark.sources.generator.GeneratorConfig;

import org.joda.time.Instant;



import java.util.Random;



import static com.bff.gaia.unified.sdk.nexmark.sources.generator.model.AuctionGenerator.lastBase0AuctionId;

import static com.bff.gaia.unified.sdk.nexmark.sources.generator.model.AuctionGenerator.nextBase0AuctionId;

import static com.bff.gaia.unified.sdk.nexmark.sources.generator.model.StringsGenerator.nextExtra;



/** Generates bids. */

public class BidGenerator {



  /**

   * Fraction of people/auctions which may be 'hot' sellers/bidders/auctions are 1 over these

   * values.

   */

  private static final int HOT_AUCTION_RATIO = 100;



  private static final int HOT_BIDDER_RATIO = 100;



  /** Generate and return a random bid with next available id. */

  public static Bid nextBid(long eventId, Random random, long timestamp, GeneratorConfig config) {



    long auction;

    // Here P(bid will be for a hot auction) = 1 - 1/hotAuctionRatio.

    if (random.nextInt(config.getHotAuctionRatio()) > 0) {

      // Choose the first auction in the batch of last HOT_AUCTION_RATIO auctions.

      auction = (lastBase0AuctionId(eventId) / HOT_AUCTION_RATIO) * HOT_AUCTION_RATIO;

    } else {

      auction = nextBase0AuctionId(eventId, random, config);

    }

    auction += GeneratorConfig.FIRST_AUCTION_ID;



    long bidder;

    // Here P(bid will be by a hot bidder) = 1 - 1/hotBiddersRatio

    if (random.nextInt(config.getHotBiddersRatio()) > 0) {

      // Choose the second person (so hot bidders and hot sellers don't collide) in the batch of

      // last HOT_BIDDER_RATIO people.

      bidder = (PersonGenerator.lastBase0PersonId(eventId) / HOT_BIDDER_RATIO) * HOT_BIDDER_RATIO + 1;

    } else {

      bidder = PersonGenerator.nextBase0PersonId(eventId, random, config);

    }

    bidder += GeneratorConfig.FIRST_PERSON_ID;



    long price = PriceGenerator.nextPrice(random);

    int currentSize = 8 + 8 + 8 + 8;

    String extra = nextExtra(random, currentSize, config.getAvgBidByteSize());

    return new Bid(auction, bidder, price, new Instant(timestamp), extra);

  }

}